Sewing machines



Dec. 4, 1962 E. SCHLOSSER ET AL SEWING MACHINES Filed Feb. 2. 1960 2Sheets-Sheet l D 4, 1952 E. SCHLOSSER ETAL 3,066,627

SEWING MACHINES Filed Feb. 2, 1960 2 Sheets-Sheet 2 INVENTOR-S [KW/A Jab105:6? By quwr/rae Ari/Ex United States Patent Ofifice 3,%5,6Z7 PatentedDec. 4, 1962 3,066,627 SEWEING MACHINES Erwin Schlesser and Gi'lntherMeier, Karlsruhe-Durlach,

Germany, assignors to Gritzner-Kayser Aktiengesellschaft,Karlsmhe-B'urlach, Germany, a, company of Germany Filed Feb. 2, 195.49,Ser. No. 6,3iiii Claims priority, application Germany Feb. 2., 1959 6Claims. ill. 112--26@) The present invention relates to sewing machinesof the kind wherein a supporting arm for the material to be sewn extendsparallel to the arm of the machine. In sewing machines of this kind, thedrive for the lower stitch-forming instruments, including the drive forthe feed dog, is fitted in the material supporting arm which isconstructed as an arm extending freely from the base of the machine.

It is very desirable to provide the material-supporting arm with thesmallest possible cross section because such a cross section makes iteasier for the operator to slip tubular sewing material over the arm,for example for the purpose of darning. It has hitherto been verydifiicult to combine such requirement with the task of constructing thedrive for the lower stitch-forming instruments, simply, cheaply androbustly. In this respect driving means which comply with suchrequirements occupy a comparatively large amount of space andnecessarily lead to a considerable increase in the cross section of thematerial supporting arm.

The object of the present invention is to provide a sewing machine whichis fitted with a freely projecting material supporting arm and in whichthe act of guiding the sewing material, particularly for the purpose ofdarning of stockings or other tubular material is facilitated andwherein at the same time a cheaply manufactured, reliably operating andeficient drive is accommodated within a minimum cross section of thematerial supporting arm.

In achieving the said object in accordance with the present invention,the material supporting arm of the sewing machine is disposed rearwardlyof the machine arm but at its free end has a cranked or short forearmpart which extends forwardly conveniently to a position below the stitchforming mechanism depending from the machine arm.

Such a construction greatly facilitates work of the operator on thesupporting arm of the machine in that both hands have convenient lateralaccess to the stitch-forming position without the operator having toapproach the machine from the front in an unaccustomed manner or withoutconstructing the machine with dimensions which exceed those of a normalsewing machine having a material-supporting arm. Furthermore, in thesaid cranked part of the material-supporting arm, which is veryimportant for the invention, the drive of a rotating looper locatedtransversely to the direction of sewing can be accommodated with the useof a pair of-bevel gears of normal dimensions and with a transmissionratio 1:2.

.A very favourable and space-saving arrangement is achieved according tothe present invention by the feature that the transmission of the risingand advancing movement to the feed dog, accommodated in the crankedpart, is effected by two levers extending one above the other and bentat right angles out of the supporting arm into the crank bend. Thismakes it possible to use for the transmission movement even the narrowpassage between the pair of bevel gears for driving the looper shaft andthe outer wall of the material supporting arm.

Further features of the invention and details of the advantages achievedthereby will be apparent from the following description of oneembodiment of a sewing machine illustrated by way of example in theaccompanying drawings in which:

FIGURE 1 is a perspective view of the machine.

FIGURE 2 shows the material supporting arm alone on a larger scale andwith the stitch plate and cover thereof detached.

FIGURE 3 is an inclined view of the machine from the rear, with thecover of the supporting arm removed.

FIGURE 4 shows the underside of the cover of the supporting arm.

FIGURE 5 is a section through the securing means for the stitch plate.

FIGURE 6 is a section taken on the line VIIIVIII of FIGURE 7.

The illustrated machine (FIGURES 1 and 3) has the usual base plate 1 onwhich is mounted a base 2 to which is connected in turn a casting whichcomprises a standard or column 3 formed integrally with an arm 4 and ahead 5. The parts fitted in the arm 4 and in the head 5 are constructedin known manner and accordingly in the drawings only those parts whichare visible from outside are shown, such as for example the needle bar6, the presser bar 7 (FIGURE 1) and the lifting lever 8 for the presser(FIGURE 3).

The material-supporting arm indicated as a whole by the reference andhaving a front wall 9a and a rear wall 91; projects from the base 2. Thesupporting arm extends parallel to the machine arm 4, but is arrangedsomewhat to the rear relatively to said arm 4. It also is formed at itsfree end with a cranked or forearm part 10 (FIGURE 1) which extendsforwardly, with the stitchforming position located near the frontthereof.

This makes it possible for an operator, when working on sewing materialwhich has been slipped over the supporting arm 9, to have accessconveniently with both hands to the side of the stitch-forming positionwithout having to approach the machine from the left. When darningtubular sewing material, this conveniently can be guided backwards andforwards transversely to the feed direction in the peripheral directionof the tubular form.

The fiat top of the supporting arm 9 is formed by a cover 11 having a.projection 12 (FIGURES 2 and 4) which engages a recess 13 (FIGURES 2 and3) of the base. Near the stitch-forming position the cover 11 is heldcentred by a screw 14 (FIGURE 2) which extends through an opening 15 inthe cover 11 and engages a threaded bore 16 in the supporting arm 9.

A finger 17 (FIGURE 4) for holding the cage of the looper 18 is mountedon the cover 11 and as shown, this facilitates assembly. In addition,the space in the cranked part or forearm part 10 for the rotating looper18 is accessible even when the cover 11 is in position due to the factthat a flap 20 is hinged to the supporting arm 9 by means of a hingejoint 19, said flap 20 defining the forward wall of the cranked part orforearm 10 and which by means of a lock spring (not shown) providedthereon, engages a recess (not shown) in the base of the supporting arm9 and in this manner is resiliently secured in the closed position.

The lower stitch-forming devices accommodated in the crank part 11 thatis to say, the looper 18 and the feed dog 22, are driven by two shaftsjournalled in the supporting arm, the rotating drive shaft 23 for thelooper and the oscillating feed shaft 24 for the feed dog.

Both shaft 23 and 24 are journalled at one end in an intermediate ortransverse wall 25 of the supporting arm 9 to which is connected anotherintermediate wall 26. The latter is provided with a bearing bushing 27for mounting the looper shaft 28 (FIG. 3). The wall 26 is continuouswith a third intermediate wall 29 in which an opening is arranged,necessary for reasons of manu- Q facture, which is closed by means of afiat plug (FIG. 2).

A first bevel gear 31 mounted on the drive shaft 23 for the looper and asecond bevel gear 32 of half the number of teeth of that of the firstgear 31 and meshing therewith and arranged on the looper shaft 28, areadapted to operate in a space bounded by the intermediate walls 25, 26and 29. The cover 11 is constructed so that suitable conformations 33,34 and 35 (FIGURE 4) of the cover 11 will come to rest on theintermediate walls 25, 26 and 29. This results in the formation of anenclosed space in which the bevel gears 31, 32 are protected againstbecoming soiled, particularly by sewing dust.

When darning, the feed dog 22 should be rendered inoperative. For thispurpose a stitch plate 36 (FIGS. 2, 5 and 6) is provided, the peripheryof which is symmetrically constructed with respect to a straight line 37(FIGURE 2) which intersects the carrier arm 9 at an angle of 45 so thatit has two equal sides 38 and 39, the side 38 of which has an archedcover 40 with stitch hole 41 and the side 39 has slots 42 for thepassage of the feed dog 22 and also a stitch hole 43. By raising thestitch plate 36 from the supporting arm 9, turning the stitch plateabout the straight line 37 as a pivot and reseating it, the part of thestitch plate 36 with the arched cover 40 or the part with the slots 42can optionally be located at the stitch-forming position, i.e. below theneedle bar 6.

For this purpose the stitch plate 36 should be turned and a rapid fixingmeans is provided for said plate, which makes it possible to secure theplate reliably in both positions Without the use of a tool such as ascrewdriver and without any parts projecting from the upwardly directedside hindering the movement of the sewing material.

A double-sided locking spring 45, which is disposed below an opening 46in the cover 11 is riveted to the angular member 44 (FIG. 5) threadedlysecured to the underside of the cover 11. A bolt 48 is arranged to beloosely displaceable in a bore 47 of the stitch plate 36 and carriesrounded heads 49 on each side of the stitch plate 36.

It will be seen from FIGURE 6 that the locking spring secured to thecover 11 retains the lower head 49 drawing it somewhat downwardly sothat the upper head 49 is drawn against the top of the stitch plate 36in a manner which does not prevent the movement of the sewing material.As shown in FIG. 6 the locking spring 45 holds the lower head 49 inslightly downwardly biased Y position, so that the upper head 49 isdrawn against the upper surface of the stitch plate 36 in a manner thatdoes not impede the passing of the material being sewn. By this meansthe stitch plate is retained in its position. In this position, thestitch plate is also centered by pins 50 (FIGURE 2) on the cover 11 andby holes 51 in the stitch plate 36.

For turning the stitch plate 36 the operator needs merely to reach underthe stitch plate 36 from a troughshaped depression 52 (FIGURES 2 and 5)in the cover 11, to raise said stitch plate against the force of thelock spring 45 in order to turn its axis of symmetry 37 and to disposeit again on the cover, taking into account the centring means 50, 51.After this it is only necessary to press in the bolt 48 and to allow itslower head 49 to engage in the lock spring 45.

In the foregoing, the invention has been described with reference to aspecific illustrative device. It will be evident, however, thatvariations and modifications, as well as the substitution of equivalentelements for those illustrated, may be made without departing from thescope and broader spirit of the invention as set forth in the appendedclaims. The specification and drawings are accordingly to be regarded inan illustrative rather than in a limiting sense.

We claim:

1. In a sewing machine having a vertical standard mounted on a base andsupporting a horizontally disposed machine arm having a machine head, aneedle bar supported in said head and extending vertically downwardlytherefrom, a material supporting arm extending from said base generallyparallel to and relatively rearwardly of said machine arm, and having afront wall and a rear wall, and a forearm part extending at right anglesto and from said suppodting arm below said machine head, said forearmpart having a forward wall disposed generally within the verticalconfines of said head, an intermediate wall substantially in alignmentwith said front wall and parallel to said forward wall, a loopersupported by said intermediate wall and a feed dog disposed on saidforearm part proximate said forward wall thereof and below said needlebar.

2. In a sewing machine having a vertical standard mounted on a base andsupporting a horizontally disposed machine arm having a machine head, aneedle bar supported in said head and extending vertically downwardlytherefrom, a material supporting arm extending from said base generallyparallel to and relatively rearwardly of said machine arm, and having afront wall and a rear wall, and a forearm part extending at right anglesto and from said supporting arm below said machine head, said forearmpart having a forward wall disposed generally within the verticalconfines of said head, an intermediate wall substantially in alignmentwith said front wall and parallel to said forward wall, a loopersupported by said intermediate wall and a feed dog disposed on saidforearm part proximate said forward wall thereof and below said needlebar, said rear wall of said material supporting arm being flush with anda continuation of said base and said forward wall being a portion of aflap hingedly connected to said forearm part.

3. In a sewing machine having a vertical standard mounted on a base andsupporting a horizontally disposed machine arm having a machine head, aneedle bar supported in said head and extending vertically downwardlytherefrom, a material supporting arm extending from said base generallyparallel to and relatively rearwardly of said machine arm, and having afront wall and a rear wall, and a forearm part extending at right anglesto and from said supporting arm below said machine head, said forearmpart having a forward wall disposed generally within the verticalconfines of said head, and a feed dog disposed on said forearm partproximate said forward wall thereof and below said needle bar, said rearwall of said material supporting arm being flush with and a continuationof said base, said material supporting arm enclosing a looper driveshaft supporting a first bevel gear adjacent said forearm part and saidforearm part enclosing a looper adjacent said forward wall thereof andbelow said feed dog and a looper supporting shaft disposed at rightangles to said looper drive shaft and having a second bevel gear inmeshing relationship with said first gear, said second gear having onehalf the number of teeth than said first gear, and said forward wallbeing a portion of a hinged flap movable to permit access to saidlooper.

4. In a sewing machine having a vertical standard mounted on a base andsupporting a horizontally disposed machine arm having a machine head, aneedle bar supported in said head and extending vertically downwardlytherefrom, a material supporting arm extending from said base generallyparallel to and relatively rearwardly of said machine arm, and having afront wall and a rear wall, and a forearm part extending at right anglesto and from said supporting arm below said machine head, said forearmpart having a forward wall disposed generally within the verticalconfines of said head, and a feed dog disposed on said forearm partproximate said forward wall thereof and below said needle bar, said rearWall of said material supporting arm being flush with and a continuationof said base, said material supporting arm enclosing a looper driveshaft supporting a first bevel gear adjacent said forearm part and saidforearm part enclosing a looper adjacent said forward wall thereof andbelow said feed dog and a looper supporting shaft disposed at rightangles to said looper drive shaft and having a second bevel gear inmeshing relationship with said first gear, said second gear having onehalf the number of teeth than said first gear, and said forward wallbeing a portion of a hinged flap movable to permit access to saidlooper, said material supporting arm having a transverse wall includingjournal means for said looper drive shaft and a wall extending into saidforearm part at right angles to said transverse wall including journalmeans for said looper supporting shaft, and said Walls including saidjournal means defining a housing for said bevel gears.

5. In a sewing machine having a vertical standard mounted on a base andsupporting a horizontally disposed machine arm having a machine head, aneedle bar supported in said head and extending vertically downwardlytherefrom, a material supporting arm extending from said base generallyparallel to and relatively rearwardly of said machine arm, and having afront wall and a rear wall, and a forearm part extending at right anglesto and from said supporting arm below said machine head, said forearmpart having a forward wall disposed generally within the verticalconfines of said head, an intermediate wall substantially in alignmentwith said front wall and parallel to said forward wall, a loopersupported by said intermediate wall and a feed dog disposed on saidforearm part proximate said forward wall thereof and below said needlebar, a stitch plate adapted to be selectively reversed into a positionfor covering said feed dog and into a position to accommodate said feeddog, said plate having a portion presenting an arcuate formation havinga needle aperture and a portion presenting slots for the passage of saidfeed dog, said portions being arranged symmetrically relative to an axisof symmetry intersecting said portions and disposed at an angle ofrelative to each of said portions.

6. A sewing machine in accordance with claim 5 comprising said stitchplate, a bore provided. along said axis of symmetry, a bolt having headsat opposite ends received in said bore, a latching spring arrangedwithin said supporting arm adapted to receive and interlock with one ofsaid heads, thereby drawing said stitch plate downwardly against saidsupporting arm and said forearm part.

References Cited in the file of this patent UNITED STATES PATENTS1,424,854 Rogers Aug. 8, 1922 1,452,696 Mock Apr. 24, 1923 2,569,091Robert Sept. 25, 1951 2,656,805 Reinhold Oct. 27, 1953 2,918,027 JohnsonDec. 22, 1959 2,944,497 Waterman July 12, 1960 2,945,461 Perla July 19,1960 FOREIGN PATENTS 896,246 France Apr. 24, 1944

